Ecologia espaço-temporal e saúde do guaxinim Procyon cancrivorus (Mammalia: Carnivora) no Pantanal central

Abstract

Medium-sized carnivore mammals have been more widely studied in the Neotropical region, with exceptions for some species, as the crab-eating raccoon (Procyon cancrivorus), a nocturnal, shy and difficult-to-capture species. Studies focusing their spatial and temporal ecology, and infection by transmissible diseases are rare or inexistent. Thus, we present data about home range, habitat and shelter use, time budget activity, relationship between the activity period and habitat use, and infection by six diseases (caused by Trypanosoma cruzi, Trypanosoma evansi, Leishmania spp., Toxoplasma gondii e Leptospira spp., besides rabies) regarding radiotracked crab-eating raccoons actively captured inhabiting the central Pantanal, a large Neotropical wetland. Their home ranges did not differed between sexes (F(1,6)=2.131, P=0.195), ranging from 0.3 to 6.6 km2 (100% MCP) and from 1.3 to 10.9 km2 (95% FK), and being similar to home range sizes of sympatric omnivorous medium-sized carnivore mammals, as brown-nosed coatis (Nasua nasua) and crab-eating foxes (Cerdocyon thous) previously radiotracked in the study area. Some pairs had large overlaps for home ranges and core areas, especially during the wet season, and for a pair of males with social bonds. Individuals positively select water bodies during active period (= 0.12, P= 0.02), and tended to select forest patches during their rest period (= 0.31, P= 0.07). Shelters more frequently used were located in the edge of forest patches, in cluster of bromeliad (47.3%), and in tussocks in seasonal flooded grasslands (38.4%). They were active from 1800 h to 0600 h, with a maximum activity between 1900 h and 0100 h, independent of sex (D= 0.055, P= 0.993). During the day, they remained in shelters, and used the crepuscular period to move to and from the shelters, across grasslands and forest patches. They usually foraged in ponds, beginning this activity at approximately 1900 h and subsequently decreasing it from 0200 h through 0600 h. Thus, differences in activity period associated with habitat use and diet can help crabeating raccoons avoid niche overlap with other coexisting medium-sized carnivores. Regarding the investigation about infections by transmissible diseases, none individual was evaluated with Trypanosoma evansi (only fresh exams). Two individuals (2/13 = 15.4%) were detected with Trypanosoma cruzi in blood culture, which was isolate to one individual and identified as TCI. The crab-eating raccoons presented antibodies to T. cruzi (9/12 = 75%), Leishmania spp. (2/3 = 66.7%), Toxoplasma gondii (3/12 = 25%), Leptospira spp. (1/12 = 8.3%; serovar Canicola) and rabies (9/13 = 69.2%). Some individuals were positive for only one disease antibodies (Chagas disease and rabies), whereas others were detected with more than one disease: Chagas + rabies (n = 3); Chagas + toxoplasmosis (n = 3); Chagas + rabies + toxoplasmosis (n = 1); Chagas + rabies + leptospirosis (n = 1); rabies + leishmaniasis (n = 2). As for the ectoparasites, ticks were found in 10 crab-eating raccoons: Amblyomma cajennense (n = 7), A. parvum (n = 52) and A. ovale (n = 10), and nymphs were not identified (n = 17). The data obtained for crab-eating raccoons in this study indicate the movement of diseases agents in the central Pantanal region, highlighting the need for a major number of studies on the epidemiology of these diseases, and public policies for the conservation of wild animals.